Greetings all!

My B18 is running great after some TLC (rebuilt SU's, electronic ignition), but find myself working from front to back and looking at replacing the muffler. In reading about performance tuning, like many of us, I want to get just a bit more out of the old humpback. I have good compression across all 4 cylinders. The delta is 145 on the low and 150 on the high side. I'm sure in the next year or so, I will remove the head and get a valve job done along with porting and polishing, and changing cams, but before that, I'm thinking about something to do before the head work.

Can anyone share their experiences with a stock B18 and adding this manifold? I want to go to a 2" exhaust system all the way back to the tailpipe. When I do, does anyone see any point in keeping the "silencer" located just under the passenger seat? The reduced back pressure will help it breath better, however I don't want to make a mistake either.